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But an efan is soooo nice. Have you looked at TurboTPI's build? Fairly stock 4.0 with a DIY turbo setup running e85. Definitely quick for what it was. And not terribly expensive, either, from what I remember.

Yea I read turbotpi's thread about a year ago, his videos made me drool. I recently bought a couple books about turbo's to get a feel for what im going to need to get my feet wet.

my thoughts have always been to stroke the thing when a rebuild becomes necessary. So if i do a turbo now, I would like to build a set up that will eventually work with a mild stroker. Problem is, I dont know how to do the math to see what CR I will have with the hypothetical stroker down the line(California only has 91 octane) let alone how that same setup will respond with 5-6psi of boost.

My goal is to study up on these topics to one day(soon) be able to wrap my head around these issues and not have to pay a shop to figure it out for me. 4.0s dont seem to be too common on this forum either
At my current level, pulling the head is a bit intimidating but im sure i could figure it out with the FSM. And i dont know how opening up the intake/exhaust ports would effect a stroker, turbo, or the combination of the two.

I have 1500 or so set aside to play with right now and want the most bang for my buck.

More airflow from a ported head will always help power. It can cost a little bit of low end torque in some cases, but not always. It'll let the motor breath better at high rpm (not as important with a stock displacement NA setup, as you CANNOT take an even remotely stock 4.0 above 5300 rpm, it takes some serious work to get around the harmonics that occur up there and can break cams and cranks). With a stroker, the ported head will keep it from being a low rpm beast that's done by 3500. With a turbo setup, it'll make more power with the same or less boost, as you're able to push more air through.

As long as you don't under-size your turbo, there's no reason a setup wouldn't scale to a stroker.

Ok, so short term im going to look into porting the Intake manifold and block. My brother is about to go through a drill tower for the Fire Department and i'll be able to use his truck until christmas. So im hoping to get the turbo set up while i have other transportation. Does valve work/porting the head affect static or dynamic CR's? My biggest concern is detonation on 91 octane. My daily driving is at sea level to maybe 300 feet but i make regular trips during the winter to the local mountains at 6k-8k feet.

This morning i was looking at possible locations to mount a turbo. The most offroad this thing see's is fire roads when im camping so im not leaving a rear/underbody mount out. Im just not too comfortable with it drawing air from underneath during rain/snow.

The engine bay is where i would like to mount one. Looks like i will have to play around with the location of the battery, fuses, and coolant reservoir to get enough space. Which makes me worried about heating up parts of the jeep that arent meant to see extreme temps...

I need to get a list of parts going so i can source the set up for as cheap as possible. Some threads on 4.0 turbo's were using 3" custom exhaust manifolds and pipes. Do you guys think my 14 gauge AFE header 2.5" outlet and pipes will work with a turbo? I'm hoping 14 gauge is thick enough to deal with the heat. its tig welded and AFE claims high quality. Hopefully it wasnt a waste.

These are the components i think i'll need. please add to the list where you guys see fit.

As for the turbo itself, I want to go with a known high quality brand. hopefully these books will help me out with the size and trim, or enough to understand the recomendations from the forums.

Fuel management and tuning seem to be the biggest hurdle with this obdII computer. I dont mind a CEL because i already have to work around CA smog with my current set up.

An intercooler. either air to air or water. Water would need a pump.

I just upgraded my injectors to 703's, would this be enough for a mild turbo?

Wideband o2 sensor.

various fittings and lines for oil to the turbo.

I have the Kolak ignition, with the msd coil. the boostwerks build talks about a step colder spark. necessary?

A BOV or wastegate to control the boost.

Heatshields and heat wraps to help with the heatsoak and protecting other components in the engine bay from seeing extreme temps.

Charge pipe

I have a great exhaust shop that knew my family back when we had shops around LA and they are willing to help me out wherever they can.

When I port the head and intake manifold, are there any special things i should use? are felpro gaskets okay?

IF anything that im posted seems misinformed or uneducated, its because i am. Let me know if it seems im diving into to something too soon.

I'd do the ported intake / head and maybe a cam swap (converting to roller cam is better than staying flat tappet both for durability with a more aggressive cam and for power). Then, after that, if you're still looking for more, you could go to a stroker and/or boost it. Turbo setup can definitely fit in the engine bay on a 4.0, it's been done before.

Yeah, and Comp makes cams for them too. Those are all flat tappet setups (like a stock 4.0 cam) though. Roller cams will have more aggressive lift rates, so they'll make more power for a given size of cam and they're not as picky about break in and oils, etc.

I was looking at 505 yesterday. The roller cam was 1200 compared to 400 for a "stage 2 kit" flat tappet. Is the difference in performance great enough to warrant tripling the price? Is the flat tappet going to be a bottle neck or problem for a boosted 4.0?

The flat tappet will certainly work fine, it'll just make a bit less power for a given size of cam (size of cam affects how it idles, etc.). Boosted or not won't matter in that sense. My personal issue with flat tappet stuff is that it's very sensitive to being broken in properly, the oil used, etc. to not wipe cam lobes with stiffer valve springs than stock (which are required with a bigger cam).

Here is an attempt to revive/update my thread. Looking back at my posts, Ive definitely learned a lot since. So I initially decided to go the turbo route and have been piecing together the parts for what seems like a lifetime. All i need is a walbro pump, a T for the oil supply from the pressure sender, and various pipes/couplings, intercooler and a wastegate.

If anyone can link me to the walbro pump that fits, the threads for the Oil pressure sender for a T, and recommendations on a size for a wastegate id really appreciate it.

I was enjoying a N/A tune from Ryan before my Torque converter went and sent metal throughout the trans. So I pulled it and am driving it over to Martin Saine for a rebuild in the next 2-3 weeks for a claimed 400-450hp rating. I now have a ceiling and a relative goal for output.

To prep for the turbo while the jeep is sitting, I am going to pull the head to do the gasket.

Do you guys have any recommendations on things to replace/upgrade while I'm in there that will benefit the build in either performance or reliability?

I have also been a click away from ordering a 505 stage 2 cam kit. Mostly due to it replacing a good amount of moving parts that have 180xxx on them. Comes with Cam, Lifters, Timing Set, Pushrods, Cambolt, Springs, Retainers, Keepers.

I wouldn't touch anything from 505 with a 10 foot stick. Horrible support, wrong parts shipped, missing parts, damaged parts, etc. You name it. Plus their roller cam is on a cast core, which is not ideal for a performance cam. Last time I saw someone use one of their kits they had ground slots in the lifter for more oiling to the cam with a grinder with an abrasive wheel. And the slots were way too large.

As for the pump the Walbro GSS342 (255LPH) and the install kit 400-869 is what you want. The pressure sending unit has 1/8" 27tpi pipe threads.

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